Heat or pressure responsive circuit closer



sept 25, 1928.

' n l. E. Back HEAT 'on rREssuRnREsPoN'slv Acmcul'r cLosEn Fuga Aug. 11. 1927 Inventor leale/'I ec/f l Q v Bv 'y ttarny i iPuente! sept. 2s, 192s.

UNITED STATES PATENT oFFlca.

lLSTB. E. BECK, F KELLY STATON, PENNSYLVANI.

naar on PRESSURE nEsroNsIvE c raetrrr cLos-E'n.

Appueauon mea August 11, 19s?. serial raalasos.

tion proceeds, ythevinvention resides in certain novel features of. construction, andin the combination and arrangement of parts as will behereinafter morefully described and claimed. j

In the drawings:- 1 Figure 1 -is -a lvertical sectional view through the device embodying the features of my invention.v

Figure 2 is a detail fragmentary vertical section through the lower portion of a modified form of the structure. i i Referring to the drawings in' detail, and

l articular-ly in the embodlment shown in x0 Figure -1, it will be seen that the numeral 1 denotes a tube of glass or equivalent mate-d rial which is provided in one side wall in termediate itsupper and lower ends with a lpocket or trap 9. The electrodes 2 and 3 enter the tube and are to -be connected to the control circuit, these electrodes are sealed in the lass or other like, material.

A bel ows or other type of expansible gas actuated element 4 is immersed in a controlling liquid such as mercury 5, the quantity of this liquid being such that when the pressure'within the' bellows is that at which it is desired to have the electric circuit closed, the level of the mercury will be such as to just close the liquid path between electrodes 2, and'3, a certain amount of mercury or like liquid being always in the ,trap 9 so as to make a quick and efficient contact. A sprin 6is disposed in the bellows and is tensione so as to 4resist the expansionof the bellows. Thisspring may' be internal as shown, ex- Aternal or a part4 of the make-up of the 'bellows itself. The tube or /onductor 7 is sealed inthe bottom of the glass tube and le connects the bellows with the vessels whse .v pressure isV to `control the electric circuit, yIf

in the bellows 4 increases,it expan jects nview as will appear as the descrip.-

desired, a modification may be used as in Figure 2, wherein this tube 7 is closed and-a certain amount of the gas and liquid may be stored therein.

The action is as` follows :-As the ressure to the point where the spring tension balances it,

so that for every pressure, there is a' givenA distension of the bellows. In expanding the bellows displaces liquid, and thus raises the mercury to the point where the circuit is A closed. Hereit is seen that the quick make and break action isl obtained by means of the cohesive gforce of the mercury, and thus eliminating the necessity of ,storingl energy 4for a Aquick make and break as has become the practice. v

. If it is desired the apparatus forja 1 temperaturecontrol, the tube 7 ma be closed as is shown in Figure 2 and t e bellows v partly'lled with some\ liquid such ascarbon-tetrachloride. l l g It is thought that the construction, operation and advanta es of this invention will now be clearly un erstood by those skilled inthis artwithout tion thereof. The present embodiment of the invention has been disclosed in detail merely by way of example since in actual` pract1ce it attains the featuresv of advantage enumerated as desirable in the statement of` the invention andthe above description. It will be apparent that changes in the details of-construction, and Ain the combination and -arran'gement of parts may be resorted to' without-departing from the spirit or scope v 1n the fluid, apair of electrodes extending a more detailed descripof the invention as 'hereinafter claimed or into the vessel so that whexf the bellows expands the fluid is displaced to cause the im,- mersion of the electrodes for closing a cirf cuit. Y

2. A device of the class described com# prisingl-a an electric conducting fluid parta y filling the l, a ows limioa mersed in thev fluid, a pair of electrodes extendinginto the vessel so' that whenjthe bellows expands the fluid is to cause tl'e lmmersionof the electrode for clogging a. circuit, said veel having e trap in the side wall thereof for holding a certain amount of said fluid and one of said electrodes in contact with the fluid in the trap at all times.

3. A device of theclass described comprisin a vessel, an electric conducting fluid partia ly fillin the vessel, a bellows immersed 1n the uid, a pair of electrodes eX- tending into the vessel so that when the bellows expands the fluid is displaced to cause the immersion of the electrode for closing a 'cil-cuit, said vessel having a trap in the side wall thereof for holding a certain amount of said fluid and one of said electrodes in contact with the fluid in the trap at all times, a spring in the bellows for normally holding the same contracted.

4. A device of the class described comprisin a vessel, an elect-ric conducting fluid parta ly filling the vessel, an expansible fluid displacing member immersed in the fluid, said vessel being formed with a trap,

and an electrode extending into the trapl iso that when the member expands to displace the fluid, said fluid will cause the contact with the electrode extending into the trap.

5. A device ofthe class described comprising a vessel7 an electricconducting fluid pands the fluid is displaced to cause the immersion of the electrodes for closing a circuit.

7. A device of the class described cornprisin a vessel, an electric conducting fluid vparta ly filling the vessel, a'pressure responslve expansible member immersed in the fluid, a pair of electrodes extending into the vessel so that when the lmember expands the fluid is displaced to cause the immersion of the electrodes for closing a circuit, said vessel having a trap in the side wall thereof for holdin a certain amount of said fluid and one o said electrodes being in constant contact with the .fluid in the trap.

In testimony whereof I affix my signature.

l LESTER E. BECK. 

